This study is a prospective, multi-centre, non-randomized, and non-blinded follow-up study to assess the efficacy and effectiveness of the ACUMED® Scapholunate Repair System in primary scapholunate interosseous ligament (SLIL) reconstruction.

The scapholunate interosseous ligament (SLIL) of the wrist can be likened to the ACL of the knee as an often-injured ligament causing joint instability that frequently impairs function and requires surgical reconstruction. Yet wrist surgeons are significantly behind knee surgeons in their ability to achieve consistent and reliable outcomes with surgical reconstruction of this ligament. This ligament is often treated using a surgical procedure of reduction and association of scaphoid and lunate (RASL). However, this procedure is accompanied with technical challenges regarding proper screw placement and trajectory.

The ACUMED® Scapholunate Repair System presents as a novel and innovated device that has the potential to improve surgeon proficiency with the RASL procedure. The purpose of this trial is to assess the efficacy and effectiveness of the ACUMED® Scapholunate Repair System in primary scapholunate interosseous ligament (SLIL) reconstruction. The study will assess the surgeon learning curve with the ACUMED® Scapholunate Repair System, record safety, complications, outcomes and adverse events for 2 years after surgery. This study will generate clinical evidence to support and maintain product registration in global markets.

Patients presenting with sub-acute or chronic (>8 weeks) primary SLIL instability that will be treated surgically at up to 20 study sites across Canada. A total of 50 wrists will be enrolled into the study and surgeons will utilize the ACUMED® Scapholunate Repair System during the surgical procedure. The study is expected to enroll all subjects within a 2-year time frame, and patients will be followed for 2 years after surgery. Subjects for whom the informed consent process has been completed and have been implanted with the study product will be considered enrolled.

At baseline, research staff will obtain data regarding participant demographics, injury characteristics, and medical history. Pre-operatively, participants will also be assessed for range of motion and grip strength and will have completed radiographs and three wrist function questionnaires, the DASH, the PRWE, and the PROMIS. Surgeons will answer questionnaires at the start of the study, after each surgical case, and at the end of the study to provide an assessment of the repair system's utility. The quality of screw placement will be graded on a newly created scale (from retrospective chart review of prior RASL procedures) to measure screw trajectory and final placement. Participants will have follow standard of care follow up timeline with preoperative visits at 2-, 8-, 12, 24- weeks, 1 year, 18 months, and 2 years. At each follow up visit, range of motion data, grip strength (after 24 weeks), and questionnaires will be completed.

Data will be reported as numbers and percentages of total for categorical data, and as mean and standard deviation of the mean with 95% confidence intervals for continuous variables. Ordinal data from the Likert scale surgeon questionnaire and screw placement grading scales will also be analyzed using parametric statistics (1, 2). Total scores from the scale items will be analyzed using the Kappa statistics. Independent sample t-tests will be used to compare the mean DASH, PRWE and PROMIS scores and for time to return to work, school, and sports. For secondary analysis, an analysis of variance will be completed for the DASH, PRWE and PROMIS scores, range of motion data and grip strength at each follow-up time interval.

Inclusion Criteria:

• Subject has primary, chronic (> 6 weeks) scapholunate instability diagnosed by X-ray, dynamic X-ray, MRI/MRI arthrogram and/or arthroscopy
• Subject is a suitable candidate for RASL repair with the ACUMED® Scapholunate Repair System
• Subject is willing and able to participate in required follow-up visits and can complete study activities.
• Subject provides informed consent

Exclusion Criteria:

• Subject has scapholunate advanced collapse wrist arthritis above grade I (styloid only)

• Subject has conditions that would eliminate or tend to eliminate adequate implant support:

  1. Blood supply limitations;
  2. Insufficient quantity or quality of bone support (osteoporosis, metabolic disorders which may impair bone formation, tumor, osteomalacia, etc.).

• Subject has mental or neurological conditions which impair their ability or willingness to restrict activities that may put the affected limb at risk.

• Subject has physical conditions that tend to place extreme loads on the implants (Charcot joints, muscle deficiencies etc.).

• Subject has neuromuscular dysfunctions (paralysis, myolysis, etc.) which could cause instability of the wrist after surgery

• Subject has an emotional or neurological condition that would pre-empt their ability or willingness to participate in the study

• Subject has an active infection - systemic or at the site of intended surgery

• Subject has a known allergy to any component of the devices used in the study

• Subject is pregnant or breast feeding

• Subject is entered in another investigational drug, biologic, or device study within 30 days of active study participation